6
MODERN MINING
February 2016
MINING News
In its latest trading update (covering the
three-month period to 31 December
2015), LSE-listed Gem Diamonds says that
it is downsizing production at its Ghaghoo
mine, located in the Central Kalahari Game
Reserve in Botswana.
During the period, Ghaghoo treated
85 046 tonnes and recovered 24 294 carats,
achieving a recovered grade of 28,6 cpht
– which is above the reserve grade. The
majority of the ore treated during the
period was sourced from tunnels 1 to 5 on
New copper discovery near Kamoa in the DRC
TSX-listed Ivanhoe Mines has announced
that the Kamoa exploration team has
made what it describes as “a new tier-one,
high-grade and flat-lying stratiform cop-
per discovery, ideally situated for low-cost
mechanised mining” in the Kakula explora-
tion area, approximately 5 km south-west of
the currently defined resources at the Kamoa
copper deposit in Katanga in the DRC.
The Kakula discovery is situated within
the 400 km
2
Kamoa mining licence area and
represents a major extension of the Kamoa
copper deposit, which the company discov-
ered in 2008. The Kamoa copper project is
a joint venture between Ivanhoe Mines and
Zijin Mining.
Two exploration drill holes completed
in late 2015 in the Kakula exploration area
– DKMC_DD996 and DKMC_DD997 – rank
among the highest-grade and highest-
grade-thickness intersections drilled to date
within the Kamoa copper deposit licence
area.
DKMC_DD996 intersected 24,16 m
(24,13 m true width) of 3,48 % copper at
a 1 % copper cut off. At a higher cut-off of
2 % copper, the intersection was 13,16 m
(13,14 m true width) of 5,26 % copper.
DKMC_DD997 intersected 18,75 m
(18,47 m true width) of 4,64 % copper at a
1 % copper cut-off and 15,17 m (14,94 m
true width) of 5,33 % copper at a 2 % cop-
per cut-off.
“The Kamoa copper deposit already is
distinguished as the world’s largest, unde-
veloped, high-grade copper discovery,”
said Robert Friedland, Ivanhoe’s Executive
Chairman. “The Kakula discovery has the
combination of significant thickness, high
grades and strike length that holds promise
for significant and rapid expansion of the
Kamoa copper deposit.
“The Kakula discovery not only shows
the potential to substantially increase the
size of the Kamoa copper deposit but also
highlights the potential for new discoveries
to the west of Kolwezi in the Congolese cop-
perbelt.”
Gem Diamonds ‘downsizes’ production at Ghaghoo
Level 1. During the period, 503 m of tun-
nelling was completed with development
well advanced in the next series of tunnels
on Level 1.
Following the sealing off of the water
fissure on Level 1, the planned intersec-
tion on the decline to Level 2 has also been
sealed.
As part of the treatment plant optimi-
sation, a 100 tonne per hour surge bin,
positioned ahead of the autogenous mill
to enhance the mill’s performance, was
commissioned on 21 January 2016. Post
commissioning, the plant achieved its tar-
geted treatment rate of 2 000 tonnes per
day, confirming the plant’s ability to run
at its nameplate capacity of 60 000 tonnes
per month.
A parcel of 49 120 carats was sold for
US$7,4 million in December 2015 (US$150
per carat), bringing the total average US$
per carat achieved for the year to US$162
per carat.
Based on the prices achieved in the
December 2015 sale and the currently
depressed state of the rough diamond
market for Ghaghoo’s production, Gem
says that various options have been
reviewed with the aim of minimising oper-
ating losses during 2016. “It is considered
prudent to downsize current production
to achieve a modified target of approxi-
mately 300 000 tonnes for 2016,” says the
company.
Gem also notes that underground min-
ing conditions experienced during the
development phase at Ghaghoo have
continued to be difficult. At the end of
November 2015, caving at the end of
tunnels 2 and 3 propagated through to
surface. Although this was anticipated
to occur as the volume of ore extracted
underground increased, it occurred some
six months earlier than expected. Due to
the safety procedures in place, no injuries
were sustained nor was there any damage
to equipment and operations at the mine
continued. Actions required to create a
buffer zone to limit sand dilution were put
in place, and underground mining was
then resumed.
It has now become apparent that the
area subject to dilution risk is greater than
originally advised and the buffer zone has
been increased following reassessment
by management, and confirmed by inde-
pendent experts. This will result in the
deferment of extraction of approximately
300 000 tonnes of ore.
Reverting back to the original Phase 1
production levels of 60 000 tonnes per
month, or expanding beyond that pro-
duction level, will be largely dependent
upon an improvement in the diamond
pricing environment. Options are being
assessed to expand the operation in order
to achieve acceptable financial returns, as
and when diamond prices improve.
Workers exiting the Ghaghoo underground mine in Botswana’s Central Kalahari (photo: Gem Diamonds).